Skiving-machine.



A. LATHAM. smvuve MACHINE. APPLICATION FILED AUG. 13. 1915.

15266927. Patnted May14,1918. v

2 SHEETS-SHEET I.

A. LATHAM.

SKIVING MACHINE.

APPLICATIONHLED AUGJB. I915-v 1 ,266,027. Pate nt-ed May 14, 1918.

'2 SHEETSSHEET 2.

UNITED STATES PATENT OFFICE.

ALBERT LATHAM, 0F BEVERLY, MASSACHUSETTS, ASSIGNOR, BY MESN E ASSIGNMENTS,

TO UNITED SHOE MACHINERY CORPORATION, OF PATERSON, NEW JERSEY, A COR-- PORATION OF NEW JERSEY.

SKIVING-M'ACHINE.

Application filed August 13, 1915. Serial No. 45,402.

chines; and I do hereby declare the fol lowing to be'a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

The present invention relates to skiving machlnes and more particularly to machlnes of this character which comprise a rotaryskiving knife and cooperating gage and" presser members for the work to the knife.

.One object of the present invention is to provide mechanism operating in an improved manner for producing a true cutting edge which may be embodied in existing machines without materially changing or modifying the machines.

A further object of the invention is to provide a simple and compact grinding mechanism operating in an eflicient manner to form the cutting edge upon a rotary skiving' knife.

With the above objects in view the several features of the invention consist in certain novel features of construction, combinations and arrangements of parts hereinafter described and claimed, the advantages of which will be obvious to those-skilled in the art from the following description.

guiding and feeding In the accompanying drawings 'illustrating the preferred form of the invention; Figure 1 represents an end elevation of a skiving machine showing the application of the improved grinding mechanism thereto; Fig. 2 is a detail showing a section in plan of the grinding mechanism and the portion of the skiving knife upon which it operrates; Fig. 3 is a section uponthe line 33 of Fig. 2, illustrating the mechanism for adjusting the grinding disk relative to the knife; Fig. 4 is a view showing m an approximate manner and upon a greatly enlarged scale the lines .which are formed upon.

the surface of the knife by the action of the grinding disk; and Figs. 5 and 6 are views partially diagrammatic, illustrating the manner in which the face of the grinding disk engages with the inner surface of the skivmg knife.

In the skiving machines of this type comprising a tubular skiving knife it has been found desirable to grind the knife upon both surfaces in order to produce a cutting edge which conforms to the true circle of rotation of the knife. In the-preferred form of the invention a bevel cutting face is formed upon the outer surface of'the knife to put the cutting edge at the opposite surface, and the inner surface of the knife is ground sufliciently-to true it up and remove any eccentricities which may be present. In existing machines of this type which are employed to a considerable extent it is customary to grind only the outer surface of the knife to form a cutting edge without grlnding the inner surface of the-knife to remove'inequalities in the surface. In order to adapt existing machines for grinding both the inner and outer surfaces of the knife toform a true cutting edge, the presspawn... of Letters Patent. P t t May 14, 1913 cut invention contemplates the provision ofmechanism which may be permanently embodied in existing machines without substantially'changing or modifying the machine, and which may be operated whenever desired to true up the edge of the knife.

- In the illustrated embodiment of the. in-

vention a skiving machine is shown of the general type disclosed in the patentto Alexander No. 1,117,541, granted November 17, 1914, and comprising a tubular skiving knife indicated at 1, rotating in a casing 3 and having a presser foot or gage member 4 supported in an overhanging arm 5. The casing is provided with a hinged portion 6 which carriesthe cooperating feed roll and actuating mechanism and which, as shown in Fig. 1, may be conveniently opened and turned back to permit access to the interior of the knife. The tubular skiving knife. 1 conveniently comprises a knife blade? which is supported upon an adjustable blade carrier 8 and is clamped in a substantially cylindrical holder 10 by clamping segments 11.. A bevel cutting face is formed upon the outer surface of the knife by a grinding disk 13 journaled ina supporting bracket 15 which may. be nioved to carry the periphery of the disk into and out of engagement with the surface of the knife, all shown and described clearly in the application above referr d to.

The inner surface of the knife is engaged by a grinding disk 20 journaled in a. head 21 which is adjustably supported in a-bracket 22 secured to the casing 3 of the machine. The bracket 22 is conveniently secured to the casing 3 by a bolt 2% and is positioned properly by projecting pins 25 which engagewith coiiperating recesses 26 formed in the casing. The disk supporting head 21 is provided with an arm 28 which is received in the sleeved portion of the bracket, as shown clearly in Figs. 2- and 3 and. is clamped in position by a transverse clamping bolt 29 which tends to draw the two split portions of the sleeve together. In the present invention the grinding-disk is supported with its face in operative relation to the surface of the knife and the engagement of the face of the disk with the surface of the rotating knife causes a rotation of the disk about an axis substantially at right angles to the axis of the knife. In the illustrated embodiment of the invention the face of the disk engages with the surface of the knife at one side of the axis of the disk and the relative rotation of the knife and disk causes the grinding of the inner surface of the knife in a series of lines which cross one another, as shown in Fig. 4, to form a finely serrated cutting edge. It will be obvious to those skilled in the art that the working face of the disk forms a. chord intersecting the curved surface of the knife at two points, the length of the chord depending upon the degree of curvature of the-knife surface and upon the location of the disk relative to the knife. This construction and mode of operation serves to grind the surface of the knife in an extremely efficient manner and with a simple mechanism and at the same time produces a highly eflicient form of cutting edge. The grinding disk preferably consists of a grinding ring 30 which is secured to a metal supporting plate 31 which is held upon the end of a spindle 32 by a clamping bolt 33, as shown clearly in Fig. 2, to present the face of the grind ing ring in operative relation to the inner surface of the knife. The spindle 32 is slidingly supported in the head 21 substantially at right angles to the axis of the knife and is normally moved in a direction to cause the engagement of'the grinding disk with the knife by a spring 35 received in a bore 36 formed in the head 21 and interposed between the head and a thrust collar 37 secured to the spindle. It will be obvious that as the grinding disk is rotated by the frictional engagement of the face of the disk with the surface of the knife the spindle 32 must be free to rotate in the head 21 and to this end the spring 35 engages with a plate 38 which. is supported by an antifriction thrust bearing 39 interposed between the plate and the thrust collar 37. The movement of the grinding disk toward the surface of the knife is limited and the operative position of the grinding disk is accurately determined by an adjustable plug e0 threadedly received in the head 21 and having its inner end engaging with the thrust collar 37, as shown clearly in Fig. 2,

to determine the position of the spindle 32.

With this construction the movement of the ginding disk in the direction of the surface of the knife is positively'limited and mechanism is provided for yieldingly main taining the grinding disk in this operative position. The grinding disk may be con veniently manipulated to remove it from engagement with the surface of the knife, or to prevent the rotation when in contact with the surface of the knife by a knurled. handle il secured to the outer end of the spin die. The head 21 is supported upon the outside of the casing 3 and projects through v ity to one another and to this end, as shown clearly in Fig. 2, the grinding disk is supported with its axis inclined slightly to the plane of rotation of the skiving knife.

in order to move the grinding disk in a rectilinear path in the direction of the knife axis, an adjusting plug 44 is threadedly received in the end of the bracket 22 and bears against the end of the arm 28, as shown clearly in Fig. 2. In order to retain the arm 28 in the bracket without turning,

the arm is provided. with longitudinal grooves or recesses &5 which are engaged by positioning screws 46 threaded in the bracket 22, as shown clearly in Fig. 3. By relatively adjusting the two screws 46 the arm may be slightly turned in thebracket 22, adjusting the grinding ring angularly in the plane of the knife edge.

The term face when applied to that portion of the grinding disk which operatively engages with the surface of the knife throughout the present specification and claims is considered as the substantially fiat face of the grinding ring, as distinguished from the peripheral surface of the ring.

/Vhile it is preferred to employ the specific construction and arrangement of parts shown and described, it will be understood that this construction and arrangement is not essential except so far as specified in the claims, and may be changed or modified without departing from the broader features of the invention.

The invention having been described,-

what is claimed is:

. 1. A skiving machine comprising a tubular skiving knife, a grinding disk engaging with one surface of the knife to form a bevel cutting face, and a grinding'disk supported in operative relation to the opposite surface of the knife with the face of the disk arranged to contact with the moving surface of the knife. v

2. A skiving machine comprising a tubular skiving knife, and a grinding disk supported in operative relation to the inner surface of the knife with a face of the disk contacting with the knife surface so that the face of the disk moves across the path 'of movement of the knife surface when the disk is rotated.

3. A skiving machine comprising a tubular skiving knife, a casing, a bracket secured to the outside of the casing, a spindle supported in the bracket and projecting within the casing, a grinding disk mounted upon the inner end of the spindle and arranged with one face in operative relation to the inner surface of theknife, .and means for moving the grinding disk into contact with the knife.

4. A skiving machine comprising a tubular skiving knife, a grinding disk positioned in operative relation to one surface of the knife, and means for supportin the disk with its face in operative relation to the surface of the knife, constructed and ar-: ranged to cause the knife surface to be' ground by the face of the disk in a series of intersecting lines to form a serrated cutting edge.

5. A skiving machine comprising a tubular skiving knife, a grinding disk, a spindle supporting the disk with-one face in opera tive relation to the surface of the knife,

means normally tending to move the face of means for removing ment with the knife.

6. A skiving machine comprising a skiv-' ing knife, a stationary bracket, a spindle slidingly supported in the bracket, a grinding disk mounted upon the end of the spindle in operative relation to the knife, a spring for normally moving the disk into contact with the knife, and an adjustable stop for limiting the movement of the disk toward the knife.

7. A skiving machine comprising a skiving knife, a casing, a bracket secured to the outside of the casing and adjustable axially of the knife, a spindle slidingly supported in the bracket and projecting within the casing, a grinding disk mounted on the inner end of the spindle and arranged to engage with the inner surface of the knife, and means for limiting the movement of ithe spindle in the direction of its length toward the knife.

8. A skiving-machine comprising a skiving knife, a bracket having a recess formed therein, a spindle slidingly mounted in the bracket, a grinding disk secured to the spindle, a spring located in the recess and normally tending to. move the grinding disk into contact with the knife, and a'sto adjustably secured in the bracket to limlt the movement pf the disk toward the surface of the knife.

' 9. A skiving machine comprising a tubular skiving knife, a grinding diskhaving one face arranged in operative relation to the inner surface of the knife, means for supporting the grinding disk with its axis of rotation inclined to the plane of the knife edge, and means for moving the disk toward the surface of the knife.

ALBERT LATHAM. 

